Isonzo

I recommend attempting this achievement on a fresh server, so from the main menu press RB so you're in the 'Play' menu. From here press Y to create a Custom Match, turn on the Friends Only setting, and choose the 6th Battle of the Isonzo Offensive starting on the Gorizia map (This works on any map with a bridge, but I found this one to be easier).

You'll need to start as the Austro-Hungarian Empire here so you can spawn in on the point at the far back of the map behind objectives A and B. Now, as of writing, the bots on your team won't cut the barbed wire you place, and we need the attackers to take both objectives to access the bridge. Spawn in as an engineer and run to the right-hand side to build the barricade (a gap in the barbed wire on the river's edge) and then move to the left to do the same to the centre, and then the left-most side. Your teammates should now all be stuck in that spawn area and all you need to do is wait for the attackers to take the two objectives.



While you're waiting, head up to the bridge on the left and hang around until you get the message to fall back. This is when you can plant the dynamite. Walk to the centre of the bridge; the left side of the broken train cart, and you'll see a red bridge icon there, that's where you place the dynamite by holding X. Fall back along the bridge a little bit and feel free to wait-out the timer by shooting the enemies crossing the river to earn progress towards the
Soča Drag achievement for killing 20 enemies that are wading in the Isonzo river.

Once the dynamite goes boom the achievement should pop! 💀🐺